In this competing renewal application, we propose to extend the purview of the current 2-year research grant to include study of the developmental course or natural history of involvement in drink-driving and risky driving in late adolescence and young adulthood. The on-going grant, just starting its 02-year, involves a large, statewide cross-sectional survey of around 3000 licensed drivers aged 18 to 25. The focus of this 1990 survey is to establish the relation of drink-driving and risky driving to each other and to a larger lifestyle reflecting conventionality-unconventionality. Both self-report and official-record data on drink-driving and risky driving behavior are being collected. The proposed research will transform the cross-sectional survey into a longitudinal study. It will permit the follow-up of the participants in the 1990 statewide survey on an annual basis in both 1991 and 1992, yielding a total of 3 waves of longitudinal data on drink-driving and risky driving and on their correlates in this segment of the population at highest risk for traffic crashes. Official driving history record data on each participant will also be obtained from .the Colorado State Division of Motor Vehicles. In addition, a face-to-face interview will be conducted with 300 young men who differ in their patterns of involvement in drink-driving and risky driving over the three waves of longitudinal data providing a more intensive understanding of the process of "maturing out" of such risk-prone behavior.